This post is the second part of my research into how nutrition affects prenatal development. I will go over my research on how nutrients affect prenatal brain development. During the prenatal and early postnatal stage, the brain is rapidly developing. Because of this, it is very vulnerable to nutrient deficiency while at the same time being at its most malleable state. It is easiest for the brain to repair itself in this stage, but its vulnerability still outweighs its malleability and as a result, negative effects from nutrient deficiencies often persist after the nutrient has been resupplied. The damage done due to malnutrition in prenatal brain development is often irreversible.
Certain nutrient deficiencies pose the greatest threat in fetal development. These include protein, iron, zinc, selenium, iodine, folate, vitamin A, choline, and long-chain polyunsaturated fatty acids. Iodine deficiency is the most common and most dangerous deficiency in prenatal development.
- The human body needs iodine to create thyroid hormones that control metabolism and for proper bone and neurological prenatal development. Iodine deficiency during pregnancy results in a multitude of neurological defects. Severe Iodine deficiency in prenatal development causes hypothyroxinemia which results in irreversible brain damage. Iodine deficiency results in neurological and/or hypothyroid cretinism, which is characterized by deaf-mutism, diplegia, squint, goitre, and mental retardation.
A landmark trial was conducted in Papua New Guinea where endemic cretinism is extremely prevalent. The controlled trial was conducted with a population of approximately 8000 people. Alternating families were given saline (the control) and iodized oil injections. Over the next four years, data on the newly born infants was collected by a doctor who did not have any knowledge as to which families had received the iodine oil, making the trial double blind. Out of the 534 children born to mothers who had not received the iodine oil, 26 were born with endemic cretinism (4.87%). Of the 498 children born to mothers who had received iodine oil, only seven were born with endemic cretinism (1.41%). This suggests that severe iodine deficiency in prenatal development results in neurological damage during fetal development. In order to prevent neurological damage, iodine supplements should be given before conception.
- When I read Dr. Hetzel's reflection on his research entitled "Commentary: From iodine deficiency in Papua New Guinea to a global programme of prevention." I found it very inspiring how he highlighted the effects of this trial on the people of New Guinea. The results they found in the study resulted in 120,000 people in Papua New Guinea being given injections of iodized oil and an iodized salt program being started to supply women with iodized oil so their babies can be born healthier. The results of this research has also brought attention from the international scientific community about the importance of iodine in the diet of pregnant mothers. The term Iodine deficiency disorder was coined as a result of this trial. Being very much a humanitarian myself, I have often wondered how my interest in science could be used to help people. This study has shown me an example of the positive effects that scientific studies can have on an international scale.
|Nutrient||Brain requirement for the nutrient||Predominant brain circuitry or process affected by deficiency|
|Protein-energy||Cell proliferation, cell differentiation||Global|
|Growth factor synthesis||Hippocampus|
|Neuronal and glial energy metabolism||Hippocampal-frontal|
|Zinc||DNA synthesis||Autonomic nervous system|
|Neurotransmitter release||Hippocampus, cerebellum|
|Copper||Neurotransmitter synthesis, neuronal and glial energy metabolism, antioxidant activity||Cerebellum|
|Myelin synthesis||White matter|
Hetzel, B. (2012). Commentary: From iodine deficiency in Papua New Guinea to a global programme of prevention. International Journal of Epidemiology, 595-598. doi:10.1093/ije/dys057. Retrieved November 5, 2015, from http://ije.oxfordjournals.org/.../ije.dys057.full.pdf
Negro, R., Soldin, O., Obregon, M., & Stagnaro-Green, A. (2013). Hypothyroxinemia and Pregnancy. Endocrine Practice, 422-429. doi:10.4158/EP10309.RA. Retrieved November 5, 2015, from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3637943/
Pharoah, P., Buttfield, I., & Hetzel, B. (1971). Neurological Damage To The Fetus Resulting From Severe Iodine Deficiency During Pregnancy. The Lancet,297(7694), 308-310. doi:10.1016/S0140-6736(71)91040-3. Retrieved November 5, 2015, from http://www.sciencedirect.com/s...ii/S0140673671910403
Zimmerman, M. (2009). Iodine deficiency in pregnancy and the effects of maternal iodine supplementation on the offspring: A review. The American Journal of Clinical Nutrition®,89(2). doi:10.3945/ajcn.2008.26811C. Retrieved November 4, 2015, from http://ajcn.nutrition.org/content/89/2/668S.full
Georgieff, M. (2007). Nutrition and the developing brain: Nutrient priorities and measurement. The American Journal of Clinical Nutrition,85. Retrieved October 3, 2015, from Nutrition and the developing brain: nutrient priorities and measurementhttp://ajcn.nutrition.org/content/85/2/614S.full
Delong, G. (1933). Effects of nutrition on brain development in humans. The American Journal of Clinical Nutrition,57. Retrieved October 2, from http://ajcn.nutrition.org/content/57/2/286S.short